Oh, sorry. You're quite right. My mistake.
Last night I recharged both the transmitter and reciever battaries.
I tried my E-firestorm again this morning. And it worked fine, but in the last couple of minutes when the car battaries where losing charge, it started to do it's weird losing connection thing again.
Is this normal!?
By the way, this is a brand new truck. Only opened on Boxing Day.